t(1;3)(p36;p21) is a recurring therapy-related translocation

Area of Science:

• Hematology
• Cytogenetics
• Oncology

Background:

• Chromosome bands 1p36 and 3p21 are recognized as recurring breakpoints in therapy-related leukemia.
• Therapy-related hematologic malignancies can arise following genotoxic exposures.

Observation:

• A specific recurrent translocation, t(1;3)(p36;p21), was identified in eight patients with diverse hematologic malignancies.
• Five of these patients had a history of chemotherapy, including alkylating agents, prior to the translocation detection.
• The t(1;3)(p36;p21) translocation was observed to emerge at relapse or advanced disease stages in some cases.

Findings:

• The study delineated the 1p36 breakpoint within the 1p35-36 region, identifying small deletions near the breakpoint in two patients.
• A deletion at 3p21.3 was also detected in one patient with myelodysplastic syndrome (MDS).
• The identified translocation occurred in various hematologic malignancies including acute lymphoblastic leukemia (ALL), chronic myelogenous leukemia (CML), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML M3).

Implications:

• The findings suggest a strong association between the t(1;3)(p36;p21) translocation in hematologic diseases and prior exposure to mutagens, particularly alkylating agents.
• This translocation may serve as a biomarker for therapy-related hematologic malignancies.
• Further research into the mechanisms underlying this translocation and its prognostic significance is warranted.